Clinton took 46.8 percent of the vote in the May 17 vote, compared to just 46.3 percent for Sanders. a margin of just 1,900 votes. That was a stark reversal from eight years ago, when Clinton walloped Barack Obama by more than 35 points in the Bluegrass State.

With the results in Kentucky, Clinton ends the Southern primary season by nearly running the table, taking 12 out of 14 contests. Sanders won only Oklahoma and West Virginia.

Given Kentucky’s Republican tendencies in federal elections, Paul, seeking his second term, is considered a prohibitive favorite, although Gray, as mayor of the commonwealth’s second-largest city and the wealthy owner of a family construction business, poses a credible challenge.

Gray is also trying to become the first openly gay man ever elected to the Senate.